Abstract
The optimal surgical strategy for Meyerding grade I degenerative lumbar spondylolisthesis secondary to spinal stenosis remains controversial. We compared unilateral biportal endoscopic (UBE) simple decompression versus UBE-assisted posterior lumbar interbody fusion (UBE-PLIF) to identify the most effective approach based on real-world data. A retrospective study of 58 patients treated between January 2022 and January 2024: 35 underwent UBE decompression; 23 had UBE-PLIF. We analyzed operative time, fluoroscopy frequency, hospital stay, cost, pain (Visual Analogue Scale for back and leg), function (Oswestry Disability Index and modified Japanese Orthopaedic Association), and surgical success (modified MacNab criteria). Radiographic outcomes (dural sac cross-sectional area, Schizas grade, lumbar lordosis, disc height, paravertebral muscle cross-sectional area, and fat infiltration) were measured preoperatively, at 3 days postoperatively, and at final follow-up. Adjacent segment degeneration was assessed via Pfirrmann grading and adjacent superior segment disc height. Baseline demographic and preoperative radiographic characteristics, including age, sex, body mass index, hypertension, diabetes, disease duration, Pfirrmann grade, and Schizas grade, were comparable between the 2 groups (all P > .05). All procedures were successful; 2 patients from each group were lost to follow-up. The UBE group had significantly shorter operative time (mean 117 vs 188 minutes), fewer fluoroscopy exposures (mean 2 vs 29), shorter hospital stay (mean 2.1 vs 2.8 days), and lower total costs (P < .05). Both groups exhibited significant leg pain relief; the UBE group showed lower back pain Visual Analogue Scale at 3 days and 1 month (P < .05). Function scores (Oswestry Disability Index and modified Japanese Orthopaedic Association) and MacNab - excellent/good rates (93% vs 90%) were comparable. Radiographically, both groups improved in dural sac cross-sectional area and Schizas grade, UBE-PLIF showed greater lumbar lordosis and disc height restoration. Muscle analysis revealed that UBE-PLIF showed a trend toward greater paravertebral muscle cross-sectional area decline at 12 months and a more significant increase in fat infiltration compared to UBE (P < .05), suggesting more pronounced muscle degeneration. No significant difference was found in adjacent segment degeneration at final follow-up. Complication rates were low and manageable. UBE decompression offers the benefits of shorter surgery, reduced radiation exposure, faster recovery, and better preservation of muscle tissue, while UBE-PLIF provides superior structural correction. Both techniques are safe and demonstrate exceptional efficacy in treating Meyerding grade I degenerative lumbar spondylolisthesis secondary to spinal stenosis.